In the next six years, global coal demand will rise 2.6 percent annually and challenge oil as the top energy source, according to the International Energy Agency.

Coal consumption will climb to 4.32 billion tons of oil equivalent by 2017, compared with about 4.4 billion for oil, the Paris-based agency said yesterday in its first Medium-Term Coal Market Report.

Usage will rise in all regions except the United States, where cheap natural gas has damped demand, the IEA said.

Demand for coal rose 4.3 percent last year, with China accounting for 67 percent of the increase to replace Japan as the largest importer of the fuel, according to the report.

“Thanks to abundant supplies and insatiable demand for power from emerging markets, coal met nearly half of the rise in global energy demand during the first decade of the 21st Century,” IEA Executive Director Maria van der Hoeven said. “Coal’s share of the global energy mix continues to grow each year, and if no changes are made to current policies, coal will catch oil within a decade.”

Countries outside the 34-nation Organization for Economic Cooperation and Development are expected to drive growth with an annual increase of 3.9 percent. Within the OECD, coal use will drop by 0.7 percent a year as US demand falls 2.5 percent a year to 600 million tons in 2017, the IEA said. Total world consumption that year will be 6.17 billion tons, up from 5.28 billion last year.

Global demand continues to be driven by Asian economies. India will increase its influence in coal markets thanks to large reserves, a population of more than 1 billion, electricity shortages and a projected increase in energy consumption, the IEA said. The country’s demand is expected to rise 6.3 percent a year to 643 million tons in 2017, the agency said.

A surge in European coal use due to low carbon emissions prices, high natural gas prices and coal supply from the US, is temporary and will decline from 2015, the IEA said.

“Increasing renewables, coal-plant retirement and more balanced gas and coal prices will decrease coal consumption in Europe,” the report said.

Australia will become the world’s largest coal exporter by 2017, shipping 356 million tons of coal equivalent, the IEA forecast.